Improvement in platform-scales



initml MICHAEL KENNEDY, OF NEWYORK, N.

Letters PatentNo. 106,17 4, dated Aug-ust 9, 1870.

IMPROVEMENT IN PLATFORM-SCALES.

The Schedule referred to in these Letters Patent and making part of the same To all whom it may concern:

Be it known that I, MICHAEL KENNEDY, of the city, county, and State of New York, have invented certain new and useful ,Improvements in Platform, Railroad, and VVeigh-lock Scales; and I` do hereby declare that the following isafull, clear, and exact description of the same, reference -be had tothe aecompanying drawings making part of this specification, ill whichy Figure 1 is a vertical section ot' one set of primary bell-clank levers, such as are used in this class of scales, showing my vimproved mode of connecting them with each other and with asecondary bell-crank lever; and l Figure 2, a top view of the said primary levers, and the mode of connecting them, and representing the secondary levell in section.

Tllefsame letters indicate like parts in both lig-4 nres.

In lthis class of scales it has been the custom to.

connect the primary levers witll each other and with the secondary lever by a rod, having closed loops to embrace the knife-edges, and, in consequence of this, the knife-edges had to be connected with theirlevers, so that they could be taken out and replaced wllenever the scales hadto be taken apart or put together. This not only increased the cost,hut rendered such parts of the scales liable to derangenlent, as their form had to be tapering, and, hence, required to be .carefully fastened, to guard against their tendency to workout, as t'lleslightest variation iu`the position of the knife-edges destroys the accuracy ot' the scales.

By my said invention, I avoid the defect above referred to.

My said invention consists in securing the bearingblocks which bear against the knife-edges of the levers in open links, and connecting the open ends of the-said links with the connecting-rolls by screw-bolts, or equivalent fastening, so. that, when connected, the open ends'of the said links are closed, and, by removing the bolts or equivalent fastening, the links, with tlheir bearing-blocks, can be. removed, and all the parts readily disconnected and reconnected without moving the knife-edges in their levers.

By reason of this mode of construction, the knifeedges can be permanently secllred iu the ends of the levers.

In the accompanying drawings a a are the primary bell-crank levers, with knifeedge journals b b resting on bearings c c.

` lheir short arms are provided with knife-edges d d,

for the platform to rest on, alld their long arms with knife-edges e e, which rest against the bearing-blocks f The secondary bell-crank lever .t is, in like manner,

provided with three knife-edges j k l, in the usual manner, and its plane ot' motion, as usual in plat-formscales, is at right angles with theplane of motion of the primary levers a a.

Each of the levers consists of two side plates and cross-bars, cast in one piece. The cross-bars are for the support of the steel fulcrum and the knife-edges ot' the lel'ers when the levers are subjected to serious strain. Tile pieces'of steel are prepared ot' an approximate shape, and inserted in the mold, and the lever cast thereon.

After cooling, the pieces of steel are driven out of the casting, the knife-edges finished and hardened, and, thus iiuished, they are again driven into the lever and fastened, where they remain as permanent fixtures, not liable to derangenlent.

This construction necessitates the use of other means for connecting the several levers than have heretofore been used, and such a means I have hereinabove described.

The two long arms ot' the primary levers a a, and the short arm of the secondary lever i, are all three connected together by three links, m n.0, and two rods, p and q.

The links extend around and are secured to the heal'- ing-blocksff/r, which bear against the knife-edges e e of the long arms of the primary levers, and k ofthe short arln ot' the secondary lever, and the ends of the said links are open, as at s s s, so that they can be taken olf or put over the knife-edges, and the opell ends have holes through them, to' receive bolts t t t, which also pass through holes ill the two ends-of the rod p and one end of the rod q, the other end of the rod q being linked, as represented, with the closed end of the middle lilik.

From the foregoing, it will be seen that, by taking out the three bolts t t t, the three links can be taken ott and put on without removing the knife-edges, and, for that reason, the knife-edges of the three levers which require to he connected, can be permanently secured to their alms, as by casting the arms onto them, as before slated, or by any other suitable means.

It will be understood that the arrangement of levers and their connections, above described, will require at least to he duplicated, for platform-scales require at least four primary levers, the number being varied for other kinds, i

And, although I have above described only the connections ofthe primary levers with each other and with the secondary level', l do not wish to be uuderstood as limiting my claim of invention to the connecting the said primary and secondary levers by my said improved method, as it will be evident that luy said invention is equally applicable to any other two or more levers which require vto be connected in as describedfthat they cnn be opened and closed, to platform-scales., connect or disconnect the levers without removing What I claim ns my inventiomnnd desire to secure the knife-edges. by Letters Patent, is- MICHAEL KENNEDY.

In combination with the knii`e-edges, permanently secured in the levers, substantially as described, thc Witnesses: arrangement of the bearing-blocks in links of the VICT. VINGENT, connecting-rod or rods so constructed, substantially G. DE SERTRAN. 

